1. Technical Field
The following relates generally to location based services (LBS) for mobile devices, and in particular to systems and methods for providing navigation information, such as routes, ETA information, search functionality, and other related functionality on mobile devices.
2. Related Art
Rush hour traffic volume, road construction, vehicular collisions, and roadside emergencies are just a few examples of the various events and circumstances that can cause traffic congestion. Due to the nature of such events traffic congestion can be difficult to predict. Although radio, television, and online news sources can provide traffic information gathered using various techniques such as highway cameras, phone-in traffic tips, satellite imagery, and road sensors; this information is stale and/or inaccurate.
Old or inaccurate traffic information can be troublesome for various reasons. For example, an alternate traffic route, which may be less convenient, is chosen due to a traffic report indicating that a traffic problem exists, which problem has since been alleviated. This can cause a commuter to take a less optimal route, which can waste fuel, cause them to be late, and cause congestion on side-roads. Conversely, a traffic report may indicate that the commuter's route is clear, when in fact an event has, in the meantime, created a traffic jam, since the traffic report is based on information that is not current.
Navigation systems typically rely on using Geographic Positioning System (GPS) fixes, in order to determine a present location, from which information such a route to a destination can be provided. However, determining a position based on received GPS signals takes time, and such time often depends on how many GPS satellite signals can be received, and the quality of such reception. Other approaches have included attempting to use triangulation based on reception of multiple cell tower identifiers and signal strength information for such cell towers. Although such approaches can produce an estimated position of the mobile device, they can be inaccurate, in that signal strength measurements can vary widely based on current topological and environmental conditions. Also, it may be more difficult in practice to obtain a number of identifiers for cell towers, in order to perform a triangulation. Using a single cell tower identifier may fail to provide sufficient accuracy, because a cell tower can serve a wide area, in some cases, such that simply connecting to that cell tower would be insufficiently precise for navigation purposes.
Therefore, advances in location determination and responsive of such location determination remain desirable, even though GPS location determination is used for the most part.